Lay a PDF out as a fold-and-staple booklet, with the pages in the order the fold actually needs. Your file never leaves this page. Everything happens in your browser, and there is no upload endpoint to send it to — that is checked by a build gate that fails if any network code reaches a tool’s bundle.
How to do it
- Drop your PDF onto the box.
- Check the sheet count and the printing instruction.
- Make the booklet, download, and print double-sided on the short edge.
Questions
Why is the page order strange?
Because a folded stack needs it that way. The outermost sheet carries the first and the last page side by side; work inwards and the pattern continues. Print it in document order and a folded booklet reads as nonsense.
Why did it add blank pages?
Each folded sheet carries four pages, so the count has to be a multiple of four. Any blanks are added at the end, which puts them inside the back cover where blank pages are expected.
Which way do I print it?
Double-sided, flipped on the SHORT edge. Flipping on the long edge turns every other sheet upside down, and it is the mistake almost everyone makes once.